Analysis of 154 T4 Colorectal Cancer Patients with Peritoneal Carcinomatosis Treated by Surgery

Objective: The purpose of this study was to observe the factors related to T4 patients who underwent surgery for colorectal cancer (CRC) with peritoneal carcinomatosis. Methods: 154 T4 colorectal cancer patients who underwent surgery in the first Affiliated Hospital of Sun Yat-sen University were included in the study between August, 1994 and December, 2005. Some clinical variables were selected and statistically correlated with prognosis. Results: The overall survival time was 91.7 months at the end of December of 2010 or death. The complete cytoreduction had significant survival benefit than the palliative surgery group. The age, location, histological grade, complete cytoreduction and liver metastasis were associated with overall survival time (OS) according to the univariate analysis (P < 0.05). In addition, Cox multivariate analysis showed that the complete cytoreduction (CCR) and liver metastasis were independent factor influencing survival. Conclusion: Compared with palliative surgery, the incomplete cytoreduction fails to improve patient prognosis. Patients performed completed cytoreduction have a relative good prognosis.

Impact of Primary Tumor Site on the Prognosis in T4 Colorectal Cancer Patients

Objective: To retrospectively analyze the prognostic differences between LCC and RCC, and to explore the occurrence of such differences in the relevant factors. Provide clinical basis for the individualization and precise treatment of CRC. Methods: The clinical and follow-up data of 155 T4 CRC patients who underwent surgery in the first Affiliated Hospital of Sun Yat-sen University between August, 1994 and December, 2005. The age, sex, family history, staging, pathologic features, DFS, OS and other information were collected. The survival of the LCC (Left colon cancer) and RCC (Right colon cancer) patients was analyzed by Kaplan-Meier method. The survival curves of the LCC and RCC patients were compared by log-rank test. Results: There are statistically significant differences in N stage, CCR, family history and histological grade between two groups. Gender, histological grade and CCR were factors associated with OS and DFS of the T4 LCC according to the univariate and multivariate analyses. In addition, only the CCR was found to be the factor associated with OS and DFS of the T4 RCC. The mean survival of the patients was 104.23 years (range, 87.32 - 121.15 years) in the T4 RCC and 76.96 years (range, 61.32 - 92.60 years) in the T4 LCC groups. The complete cytoreduction had significant survival benefit than the palliative surgery group. Conclusion: The T4 RCC patients with CCR had a relatively better prognosis than LCC. Compared with palliative surgery, the incomplete cytoreduction fails to improve the prognosis of patient.

Energy-Efficient Deployment of Water Quality Sensor Networks

Water quality sensor networks are promising tools for the exploration of oceans.Some key areas need to be monitored effectively.Water quality sensors are deployed randomly or uniformly,however,and understanding how to deploy sensor nodes reasonably and realize effective monitoring of key areas on the basis of monitoring the whole area is an urgent problem to be solved.Additionally,energy is limited in water quality sensor networks.When moving sensor nodes,we should extend the life cycle of the sensor networks as much as possible.In this study,sensor nodes in non-key monitored areas are moved to key areas.First,we used the concentric circle method to determine the mobile sensor nodes and the target locations.Then,we determined the relationship between the mobile sensor nodes and the target locations according to the energy matrix.Finally,we calculated the shortest moving path according to the Floyd algorithm,which realizes the redeployment of the key monitored area.The simulation results showed that,compared with the method of direct movement,the proposed method can effectively reduce the energy consumption and save the network adjustment time based on the effective coverage of key areas.

Coverage Control for Underwater Sensor Networks Based on Residual Energy Probability

Underwater sensor networks have important application value in the fields of water environment data collection,marine environment monitoring and so on.It has some characteristics such as low available bandwidth,large propagation delays and limited energy,which bring new challenges to the current researches.The research on coverage control of underwater sensor networks is the basis of other related researches.A good sensor node coverage control method can effectively improve the quality of water environment monitoring.Aiming at the problem of high dynamics and uncertainty of monitoring targets,the random events level are divided into serious events and general events.The sensors are set to sense different levels of events and make different responses.Then,an event-driven optimization algorithm for determining sensor target location based on self-organization map is proposed.Aiming at the problem of limited energy of underwater sensor nodes,considering the moving distance,coverage redundancy and residual energy of sensor nodes,an underwater sensor movement control algorithm based on residual energy probability is proposed.The simulation results show that compared with the simple movement algorithm,the proposed algorithm can effectively improve the coverage and life cycle of the sensor networks,and realize real-time monitoring of the water environment.

New Approach to Lightning Strike Risk Assessment of Wind Farm

In the past,lightning strike risk assessment of buildings mainly referred to the Protection against Lightning—Part 2:Risk Management(IEC 62305-2-2010)based on protection angle method.Lightning strike risk assessment of wind farms was conducted according to the Lightning Protection for Wind Energy System(IEC 61400-24-2019),which proposed the method of lightning strike risk assessment for wind turbine.In fact,the basic idea of the two is the same,that is,the source of the lightning strike wind turbine is transformed from the former S1-S4 to the latter N D-N DJ.According to the above method,wind farm was evaluated,and it has been proved that the practice can not achieve good results.After 2018,China has issued the Guide to Evaluation of Lightning Protection Technology in Buildings(T/GZLY 3-2022)and the Technical Specifications for Lightning Interception in Forest Areas(T/LYCY 4062-2024)based on semicircle protection,in which the source of risk defined by lightning point was closer to the reality,highly targeted and effective.Taking offshore wind farm as an example,this paper introduced a new method of establishing six evaluation indicators to determine the risk level according to the principle of compliance and the new protection technology of semi-circular method,which can be used as a reference for technical personnel.

Comparisons of AGRI/FY-4A Cloud Fraction and Cloud Top Pressure with MODIS/Terra Measurements over East Asia

Fengyun-4 A(FY-4 A),the second generation of China’s geostationary meteorological satellite,provides high spatiotemporal resolution cloud products over East Asia.In this study,cloud fraction(CFR)and cloud top pressure(CTP)products in August 2017 derived from the Advanced Geosynchronous Radiation Imager(AGRI)aboard FY-4 A(AGRI/FY-4 A)are retrospectively compared with those from the Moderate Resolution Imaging Spectroradiometer(MODIS)aboard Terra(MODIS/Terra)over East Asia.To avoid possible errors in the comparison caused by the lower temporal coverage of MODIS/Terra products compared to that of AGRI/FY-4 A over the same region and to account for time lags between observations of the two instruments,we construct datasets of AGRI/FY-4 A CFR and CTP to match those of MODIS/Terra in each scan over East Asia in August 2017.Results show that the CFR and CTP datasets of the two instruments generally agree well,with the linear correlation coefficients(R)between CFR(CTP)data of 0.83(0.80)regardless of time lags.Though longer time lags contribute to the worse consistency between CFR(CTP)data derived from observations of the two instruments in most cases,large CFR/CTP discrepancies do not always match with long time lags.Large CFR discrepancies appear in the vicinity of the Tibetan Plateau(TP;28°–45°N,75°–105°E).These differences in the cloud detection by the two instruments largely occur when MODIS/Terra detects clear-sky while AGRI/FY-4 A detects higher values of CFR,and this accounts for 61%of the CFR discrepancy greater than 50%near the TP.In the case of CTP,the largest discrepancies appear in the eastern Iranian Plateau(IP;25°–45°N,60°–80°E),where there are some samples with long time lags(20–35 min)and fewer daily data samples are available for computing monthly means compared to other regions since there are many clearsky data samples there during the study period.